Wall corner construction

ABSTRACT

1,187,304. Tanks in ships. TECHNIGAZ. 18 May, 1967 [20 May, 1966], No. 23061/67. Headings B7A and B7S. [Also in Division F4] A generally rectangular liquefied gas storage container comprises an inner liquid-containing tank formed of primary and secondary barrier walls 17, 16 of Fig. 2 of thin flexible corrugated metal surrounded by heat insulation material e.g. foamed polyurethane (not shown) and which is itself surrounded by a rigid supporting wall structure, e.g. a ship&#39;s hull 1, and the spaced adjacent edges 2&lt;SP&gt;1&lt;/SP&gt;, 2 of the inner tank and support structure, and referred to as corners are connected together by longitudinally spaced cleats 5, Fig. 3, of heat insulating material e.g. wood bolted at 6, 7 to the hull and at 8, 9 to a flange 10 of a pair of nested inner and outer angle plates 3a, 3b to which are secured the primary and secondary barriers 17, 15. Stiffening members 13 secured by brackets 14 to either side of each cleat 5 extend between the hull 1 and the plate 3b. The gap between successive angle plates 3b is covered by an angle piece 20 of the same material as the secondary barrier 16 whilst the gap between successive plates 3a is covered by pieces 25 of the primary barrier 17. Each corner (53&lt;SP&gt;1&lt;/SP&gt;), Fig. 9 (not shown), formed by the intersection of three walls of the tank is also connected to the adjacent corner (53) of the hull by three spaced cleats (56a, 56b, 56c) straddling the three dihedral angles and bolted to a trihedral angular element (54) formed of nested inner and outer corner plates (54a, 54b).

Oct. 14, 1969 J, ALLEAUME 3,471,983

WALL CORNER CONSTRUCTION Filed May 19, 1967 '7 Sheets-Sheet 1 U) QT le?.hij" V 1 lvENToR .JEAN ALLEAUME ATTO EYS Y Oct. 14, 1969 J. ALLEAUME3,471,983

WALL CORNER CONSTRUCTION I Filed May 19, 1967 '7 Sheets-Sheet 2 INVENTORJEAN ALLEAUME 9M@ ATTCR EYs Oct. 14, 1969 Filed May 19, 1967 J. ALLEAUMEWALL CORNER CONSTRUCTION 'T Sheets-Sheet 3 INVENTOR JEAN ALLEAUME ATTOREYS J. ALLEAUME 3,471,983

WALL CORNER CONSTRUCTION 7 Sheets-Sheet 4 Oct. 14, 1969 Filed nay 19,19e? INVENTOR JEAN ALLEAUME @,/l'fd/ ATTOR EYS Oct. 14, 1969 J. ALLEAUMEWALL CORNER CONSTRUCTION 7 Sheets-Sheet 5 Filed May 19, 1967 INVENTORJEAN ALLEAUME Oct. 14, 1969 J. ALLEAUME 3,471,933

WALL CORNER CONSTRUCTION Filed May 19, 1967 7 Sheets-Sheet 6 INVENTORJEAN ALLEAUME ATTOR Oct. 14, 1969 J, ALLEAUME 3,471,983

WALL CORNER CONSTRUCTION Filed May 19, 1967 7 Sheets-Sheet V I l l lINVENTOR JEAN ALLEAUME ATTORN YS United States Patent O 3,471,983 WALLCORNER CONSTRUCTION .lean Alleaume, Saint Cloud, France, assignor toTechnigaz, Paris, France, a company of France Filed May 19, 1967, Ser.No. 639,881 Claims priority, applicationzFrance, May 20, 1966,

2 2 im. ci. E041 1/739, 2/60; Eo4h 7/04 U.S. Cl. 52-276 21 ClaimsABSTRACT OF THE DISCLOSURE The present invention essentially relates toa structural arrangement forming a corner construction for a wall withat least two intersecting or meeting sides or faces, having theconfiguration of a salient or re-entrant solid angle in space of anyshape, projecting inwards into or outwards from the inner wall of a forexample fluidtight and heat-insulated confining enclosed space, deningin particular a tank or the like, preferably of the so-called integratedtype, as well as the method of making said arrangement and the variousapplications of the latter.

Tanks are already known, which are adapted for example, but notexclusively, to the transport or conveyance and/ or to the storage andpreservation of fiuids kept at a temperature very different from theambient, normal or ordinary temperature, such as for example cryogenicor strongly cooled fluids and more especially liquefied gases at verylow temperature and at a pressure approaching for example the ambientatmospheric pressure, such tanks being also able to be used at hightemperatures and/ or pressures. Tanks adapted for such a purpose areadvantageously of the so-called integrated type, such as for instancethe tanks for transporting or conveying liquefied natural gases, such asliquid methane, directly incorporated into the hull of a transportingship. Such a tank generally comprises an inner envelope, shell orcasing, mostly made from metal-sheets or foils, of a metal such asstainless steel, capable of sustaining the low service or operatingtemperatures and forming a socalled impervious primary barrier, adaptedto be in direct Contact with the contents. This primary barrier isrelatively thin and exible or yieldable and preferably corrugated orcreased, generally along at least two sets or systems of corrugationsextending in substantially parallel spaced relationship in a same set orsystem and intersecting substantially at right angles the corrugationsof the other set or system so as generally to form a kind of network ofsubstantially orthogonal pattern the crests of corrugations of which arepreferably all projecting from a same inner side or face of saidmetal-sheet. This primary barrier thus forms a kind of membrane bearingpreferably in a substantially uniform manner against an outersurrounding supporting and self-carrying or rigid structure, constitutedfor instance by the ships hull and this, through the medium of at leastone layer or sheet of heat-insulating materials or lagging, wherein maybe JCC interposed or embedded at least one intermediate envelope, shellor casing, forming an impervious secondary barrier, surrounding orencompassing the primary barrier and of a configuration often similarthereto. This intermediate insulating material is thus adapted totransmit to the outer self-carrying supporting structure, all the forcesexerted or applied on the primary barrier by the contents thereof orconfined thereby.

Such integrated tanks may of course exhibit any geometrical shape, butthey frequently are of a substantially or approximately prismatoidal orparallelepipedic and even possibly cylindrical shape. These tanksgenerally embody wall corners formed by the intersection or meeting oftwo or more wall faces or sides. At each Vertex or apex of thegeometrical solid body formed by the tank, the corresponding cornerconstitutes a solid angle formed by the intersection of three or morefaces or sides converging towards or meeting at the common point formingthe vertex or apex. When such faces or sides are plane and thereforeintersect each other two by -two along a straight line or edge ofintersection, the corner formed by said solid angle is polyhedral (forexample trihedral in the case of a parallelepipedic tank), each pair ofadjacent faces or side-walls of which forms a dihedron. However, thefaces or wall sides forming said solid angle may also be skew, that iswarped, curved, convex or concave surfaces and intersect each otheralong a curvilinear edge-line, the plane angle between two adjacentfaces being then also curvilinear. Of course, in the case of acylindrical tank for example, there are no corners in the form of solidangles, but only the two corners the lateral surface forms with the(plane, dished or `bulged) heads or bases of the cylinder and thereforecomprising each one two faces intersecting along a curvilinearedge-line.

The tanks more especially of a general prismatoidal or polyhedral andmore particularly parallelepipedic shape may exhibit inner corners orsolid angles, such as dihedron or trihedrals, which may be eithersalient or re-entrant. In the prior known constructions, it occurs thatthe angular spacing or dihedral angle of each pair of adjacent faces ofthese corners or solid angles tends to vary, that is to open or increaseor to close or decrease more or less under the inuence of inner or outerpressures applied to the wall, and this is a serious inconvenience. Onemain object of the present invention is to obviate or to remove such adrawback by providing a corner or solid angle construction rigid enoughto be substantially nondeformable, that is to render substantiallyinvariable the angular spacing of each pair of adjacent faces, formingfor example a dihedron, or at the very least to obtain that anyvariation of this angular spacing.

The invention is also concerned with the process of making the aforesaidconstruction, resulting from the design of the latter.

Finally, the invention is also directed to the various applications andappliances resulting from the use or Working of constructions of thetype broadly set forth hereinabove, as well as to the variousconstructions, systems and buildings which are provided therewith, suchas preferably closed vessels or enclosures for example integrated intoor combined with an outer self-carrying, stationary or movable support,and defining an insulated space for containing or confining a product,device or apparatus, such vessels or enclosed spaces forming inparticular containers, tanks, vats, cisterns, reservoirs or the like forstoring and preserving a product, erected at a stationary position orincorporated into transport or conveying vehicles of any kind, forexample floating or rolling vehicles, as well as the safety, protectingor shielding casings, shells or vessels for nuclear plants and thenuclear reactor vessels, tanks or casings or the like.

The invention will be better understood and further objects, featuresand advantages thereof will appear as the following detailed explanatorydescription proceeds, with reference to the accompanying diagrammaticdrawings, given by way of examples only illustrating several forms ofembodiments of the invention, as applied to a tank of a generalsubstantially parallelepipedic shape. In the drawings:

FIGURE 1 shows a fragmentary, perspective and somewhat exploded view,with parts broken away, of a corner construction in the shape of are-entrant dihedral angle, according to the invention;

FIGURE 2 is a side view in cross-section taken upon the line II-II ofFIGURE 3, of the preceding construction with parts broken away;

FIGURE 3 is a top view in multiple cross-section taken upon the linesIII- III of FIGURE 2, of the preceding construction;

FIGURE 4 is a partial view, similar to that of FIG- URE 2 and showing analternative embodiment or modiiication of the fastening arrangement ofthe primary barrier;

FIGURE 5 is a prole or side-face view, in cross-section taken upon theline V-V of FIGURE 6, of a salient dihedral-shaped corner constructionaccording to the invention;

FIGURE `6 is a front view, in section taken upon the line VI--VI ofFIGURE 5, with parts broken away;

FIGURE 7 is a top view of the construction shown on FIGURE 5;

FIGURE 8 is a partial sectional view of a detail of an alternative ormodified fastening arrangement of the primary barrier;

FIGURE 9 is a fragmentary cross-sectional view, with parts broken away,of a re-entrant trihedral corner construction according to theinvention;

FIGURE 10 is a partial view in section taken upon the line X--X ofFIGURE 9;

FIGURE 11 is a fragmentary view in section taken upon the line XI--XI ofFIGURE 9.

According to the illustrative form of embodiment shown on FIGURES l, 2and 3, the reference numeral 1 denotes a self-carrying outer supportingstructure, formed for example by the double wall of a ships hull in theregion of a corner 2 having the shape of a re-entrant dihedral angleinside of which is mounted the corresponding reentrant dihedral corner 2of the integrated tank. The plane or straight angle of this dihedron issubstantially orthogonal or right in the example shown, but it can ofcourse be of any value, for example an obtuse or acute angle. Likewise,instead of having substantially generally plane faces or sides, it mayhave skew faces or possibly mixed or combined that is plane and skewfaces. The rigid and solid structure of this angle 2 consists of aseries or row of dihedral-shaped angular elements 3, preferably but notcompulsorily all identical with each other, spaced from each other,facing towards the same direction and substantially aligned in a rowextending along the edge of the dihedron 2. Such a breaking or dividingup or splitting of the solid structure of this dihedral angle 2 intoseveral spaced elements, parts, portions, pieces or sections of adihedron is necessary to allow the thermal deformations and strains ofthe impervious, relatively thin and flexible, membrane-like primary andsecondary barriers which are adapted to be rigidly secured to theangular elements and in particular, the expansions and contrac- *ionsparallel to the direction of the edge of the dihedron. ,.lthough eachangular element 3 may possibly be made of one single piece, it isadvantageous, to simplify the manufacture and mounting or erection, thateach angular element 3 consist of two inner or primary and outer orsecondary angle members 3a, 3b, respectively, which are overlying orcoupled so as to be nested or fitted into each other. Each primary anglemember 3a is made integral with the secondary angle member 3b which isassociated therewith, for example by screws or the like 4 the head ofwhich is preferably sunk or embedded in a counter-bored recess of theangle plate 3a, in order that it does not raise or project from theinner face of the angle plate. Each screw 4 is screwed in a blindthreaded hole of the secondary angle plate 3b, so that in case of abreakage or failure of the primary barrier, no leakage can occur throughthe fastening holes for the screws. Each angular element 3 is supportedby one or several supporting or carrier spacer blocks 5 consisting eachone of a connecting cleat or dog or the like, made from a compact andheat-insulating material, such as for example plywood, compressed wood,laminated wood or the like. Each spacer block or cleat is adapted ordesigned to connect the angular element supported thereby to the outerrigid supporting structure 1, such as the doublewalled hull of the shipand is preferably recessed so as to minimize any heat transmittingbridges or conductive connections. Each spacer block or cleat 5 issecured to the inner wall of the outer structure 1, in the re-entrantdihedral corner thereof, by stud pins, bolts or the like 6, for exampleby means of studs welded to the Wall 1. Each cleat is thus appliededgewise against both faces of the dihedron formed by this wall 1 andextends between pairs of registering or opposite studs, disposed oneither side of the cleat, respectively and holding same by means ofclamping or tightening strips or bars 7, extending through a recess orcut-out portion of the cleat. All the recesses or cut-out portions ofthe cleats as well as the hollow or void spaces left thereby are adaptedto be subsequently lilled with insulating material, not shown, whichwill subsequently iill up all the intermediate space between thesecondary barrier and the outer supporting structure. This insulatingmaterial may advantageously consist of a suitable synthetic orartificial material s uch as a foamed plastic material such as expandedpolyurethane or the like, applied by spraying by means of a spray-gun orthe like. The inner edge of each cleat 5 is cut out or shaped to conformto the angular element 3 to be supported thereby, that is, in the shapeof a reentrant dihedral angle wherein the secondary angle plate 3b isapplied thereagainst by its outer face which is thus conformed to by thecleat. Each secondary angle plate 3b is firmly atiixed or securedagainst each one of the cleats 5 supporting same, by one or severaltie-rods, bolts or the like 8, fastened each one to the angle plate 3b.Each tie-rod consists desirably of an eye-bolt or the like, pivotallyconnected, through the medium of a pin 9 to a clevis, lug, bracket orlike flange or member 10, integral with the angle plate 3b (FIGURE 3).Each bolt such as 8 desirably extends edgewise through the cleat 5 toproject by its screw-threaded end adapted to receive a clamping nut,into a recess or cut-out of said cleat so that such nuts be easilyaccessible. The tightening of each nut against the edge of thecorresponding recess or cutout portion of the cleat is desirablyeffected through the medium of a boat-shaped washer, a yoke or strap, acramp, a clip or the like 11, conforming to the local shape ofthe edgeof the recess or cut-out. The cleviscs 10 consist advantageously of apair of substantially parallel stitfening or reinforcing members orlianges, welded to the outer face of the angle plate 3b and betweenwhich the corresponding cleat 5 is fitted. To avoid any deformation ofthe angle plate 3b when welding the stiffeners 10, the latter areprovided with slots, notches or jags 12 along their edge bearing againstthe angle plate 3b.

When each angular element 3 is relatively long, it is supported byseveral spaced cleats, whereas when it is relatively short, it may onlybe supported by a single cleat disposed substantially in the medialtransverse plane of the angular element. In this case, since each cleat5 is generally of a substantially flat shape, there is provided, toprevent any tilting of the angular element 3 transversely towards eitherside of the cleat, at least one pair and preferably two pairs ofstiifening members or ribs 13, preferably consisting of the samematerial as the cleat 5 and bearing substantially at right anglesagainst same on either side of said cleat. Each reinforcing member 13also bears by one end thereof against the Wall of the structure 1 and bythe opposite end against the outer face of the angular plate 3b. Eachone of these reinforcing members 13 may be secured in a simple manner tothe cleat 5, for example by at least one pair of connecting cornerplates or angles 14 secured to the cleat 5 and to the reinforcing member13 by bolts such as 15. In the example illustrated, each angle plate 3bis secured by three tie-rods 8 one of which is arranged in the bisectingplane of the dihedron and the two other ones are respectively at rightangles to both flanges or faces of the angle plate 3b. In view of theirpivotal connection, these two latter tie-rods are capable of swinging orpivoting within the corresponding recess or aperture of the cleat tofollow the thermal deformations of the angle plate (see FIGURES 2 and3).

The metal sheets of the primary and secondary barriers 17 and 16,respectively, may assume the shape shown on FIGURE l, that is exhibitfor example an orthogonal pattern of corrugations arranged in twointersecting systems, sets or series of parallel spaced corrugationsdening therebetween smooth or uncormgated areas, for examplesubstantially flat or plane and defined by a substantially rectangularor square contour. The patterns or configurations of the corrugations ofboth primary and secondary barriers, respectively, may be similar to oridentical with each other or different from each other. In the presentexample, the spacings or pitches of the corrugations of both barriersare substantially identical with each other, so that the corrugations ofboth barriers differ somewhat from each other by their shape and size.The secondary barrier 16 is connected or attached in a fluid-tight manerto the respective flanges or sides of the secondary angle plates 3b `andfor this purpose, each secondary angle plate 3b comprises, on theperiphery of each flange lthereof and on the Side of the inner face, areduced, thinned or edged olf marginal portion, forming a rabbet or thelike 18, machined into the angle plate to form thereby a marginalshoulder, recessed with respect to the inner face of the flange. Againstthis shouldered edge strip of the angle plate 3b is applied the edge ofthe secondary barrier 16, all along the flanges or faces of the angleplates 3b. On each flange or face of angle plate 3b, the barrier 16 issecured by welding, for example by an arc-welded lap-joint along itsedge at 19. The secondary barrier is so directed that its corrugations,which are all projecting from a same side of the metal-sheet, are facingoutwards. Each spacing or gap left between two successive angle plates3b is covered from the outside by an angular piece 20, conforming to theshape of the angle plate 3b and preferably consisting of a sheet portionof the secondary barrier, so as to exhibit at least one corrugationextending in parallel relation to the spacing or gap between the twosuccessive angle plates 3b and straddling such a spacing or gap. Eachangle piece 20 covers by the ends of its flanges, the edge of thesecondary barrier secured to the flanges of the angle plates 3b and iswelded, for example arc-welded according to a lap-joint to saidsecondary barrier at 21. All the `welds are continuous and the coveringor overlapping between the secondary barrier and the angle piece isachieved owing to the presence of a crease or the like, formed in eachcovering angle piece to take up or compensate for the thickness of thecovered secondary barrier. Moreover, in general, each portion ofcovering metal-sheet or foil of an assembly with mutually overlappingedges preferably comprises such a crease or the like, known per se,corresponding to the thickness of the portion of covered metal-sheet orfoil.

Each angle piece 20 extends over the whole width of the flanges of eachangle plate 3b and is secured to said angle plate outside of thecovering or overlapping areas of the secondary barrier by a continuouswell along its edge.

Each primary angle plate 3a is preferably thinner than the associatedsecondary angle plate 3b and larger so as to protrude, for example alongits whole periphery, in overhanging relationship beyond the secondaryangle plate 3b. The primary barrier 17, the corrugations of which allprojecting from a same side are directed or facing inwards, that is, inthe direction opposite to that of the corrugations of the secondarybarrier 16, bears with its edge against the edge of the anges of theprimary angle plate 3a and is secured thereto. In the example shown onFIGURES 2 and 3, the primary barrier 17 is secured to the anges of eachprimary angle plate 3a, respectively, by screws or the like 22, screwedinto strips or small plates or into a strip forming a backing pla-te, orthe like, 23, fastened, as by welding, to the protruding portion of eachflange of angle plate and behind or rearwards thereof, that is on theoutside. The head of each screw 22 is preferably sunk or embedded in arecess or the like, machined, milled, counter-bored or cut in the innerface of the primary angle plate 3a.

According to the alternative embodiment or modification shown on F'IGURE4, the screws 22 for fastening the primary barrier 17 to the primaryangle plates 3a may be replaced by spot or tack welds, effected forexample by arc-welding, such as 24, extending through the primarybarrier 17, thereby avoiding any piercing or drilling thereof as well asthe fastening of small plates 23. Inner or primary angle pieces 25,respectively homologous of the outer or secondary angle pieces 20 areprovided to straddle the gaps or spacings separating the successiveprimary angle plates 3a. These angle pieces 25, which are preferablymade or taken from a primary barrier sheet-metal and comprise onecorrugation bridging Ithe gap or spacing between two primary angleplates 3a, conform to the inside shape of the primary angle plates 3aand connect to each other the portions of primary barrier 17 secured tothe anges of each primary angle plate, respectively. To this end, thecentral corrugation of each angle piece 25 is connected preferably bywelding to the corresponding corrugation of the primary barrier,substantially in aligned or registering relation to this corrugation.Each angle piece 25 is long enough, in parallel relation to the edge ofthe corner or dihedron so that the successive angle pieces arepreferably alternately overlapping by their adjacent edges which areconnected in sealing relationship by a continuous Weld along a lap-jointand also cover the edges of the secondary barrier at both ends of theflanges of the primary angle plates. To this end, each angle platecomprises a creased or swaged portion adapted to take up or tocompensate for the thickness of the primary barrier (see FIGURE 2).Outside the areas where each angle piece covers or overlaps thesecondary barrier, each angle piece is secured to the primary angleplates 3a which it connects by spot or tack welds, for example carriedout by arc-welding, such as 26 (see FIGURE 3). Thus, according to theembodiment used, when the screws 22 or spot or tack welds 24 forfastening the primary barrier I7 to the primary angle plates 3a break orfail, then the spot or tack welds 2-6, Securing the angle pieces 25 tothe primary angle plates 3a, provides the necessary mechanical strength.The fluid-tightness at each screw 22 or each spot or tack weld 24 isachieved owing to the overlapping or covering of the sheet-metal of theangle piece 13, overlying or extending over said screws or said spot ortack welds.

FIGURES 5, 6, 7 and 8 show the solution adopted in the case of a salientwall corner, for example of a salient dihedron 27 of the inner wall ofthe double-walled ships hull 1, to which corresponds the salientdihedron 27 of the inner wall of the integrated tank. Here, also, as inthe case of the re-entrant dihedron, the construction of the dihedralangle consists likewise of the spaced angular elements 28, arranged ordistributed along the edge of the salient dihedron and consisting eachone advantageously of a pair of primary and secondary angle plates 28aand 28b, respectively, nested or `fitted into each other yand havingtheir concavity facing outwards, so as to be convex inwards or towardsthe inside of the tank. Apart from their reversed orientation, thesepairs of angle plates have a configuration and assembly similar to thoseof said angle plates of the re-entrant dihedron. Moreover, the secondarybarrier 16 and the primary barrier 17 are secured to the angle plates28a, 28b, in a manner similar to that of the re-entrant dihedron andinner or primary and outer or secondary angle pieces, respectively, areprovided at each spacing or gap left between successive 'angle platesand are similarly fastened. Such primary angle pieces have been denotedby the reference numeral 29 (see FIGURES 5 and 7), Whereas the secondaryangle pieces have been designated by the reference numeral 30 (seeFIGURE 6). The coupled angle plates 28a, 28b are joined together byscrews 31. On FIGURE 5, the primary barrier is attached by spot or tackwelds, for example carried out by arc welding, to each primary angleplate 28a, whereas FIGURE 8 shows the alternative embodiment where theprimary barrier 17 is fastened to each primary angle plate 28a by screwssuch as 32 screwed into a corresponding backing plate 33, integral withsaid primary angle plate.

The angular elements 28 are supported or carried by assemblies 34,distributed along the edge of the salient dihedron and comprising eachone a box-shaped member or like casing 35, for example made from wood,secured to the supporting structure 1 forming the doublewalled shipshull and exhibiting inwards or towards the inside, two faces 36 meetingaccording to -a salient angle similar to the salient corner or dihedronand on the edge of which are fastened straddlewise, along the latter, aseries of spaced brackets or spacers 37, carrying the secondary angleplates 28b and integral therewith.

`Each box-like member or casing preferably consists of a series ofconnecting spacer blocks formed of cleats or the like 38, made forexample from wood and preferably recessed, cut out or apertured, whichcleats are secured to the supporting structure or double-walled hull 1,in straddling relation to the dihedral angle thereof. Such a fasteningis elected preferably in a manner similar to that shown on FIGURES 2 and3 in the case of the re-entrant dihedral angle, that is, by pairs ofstud pins 39, welded to the wall of the structure 1 and clampingstirrups or straps 40. These cleats 38 are for example equally oruniformly spaced from each other. The cleats of a same box-like member34 are covered or lined inside by an angle member 41, for example madeof plywood, which angle member may consist, to simplify the manufacture, of two boards or plates of plywood, joined angularly togetherat a salient angle by at least one inner connecting angle 42 secured toboth plates or boards for example by screws 43 extending through saidplates or boards and screwed directly into the angle 42. The successiveadjacent box-like members, distributed along the salient dihedron 27 andstraddling the latter, are spaced or separated from each other by gapssuch as 46 (see FIGURE 6) adapted to allow for thermal stretch orexpansion of the box-like members. Two successive boxlike members arepreferably made integral with each other by at least one system ofplates, fish-plates or the like 44, fastened by bolts to both adjacentpanels 41 of the two adjacent box-like members. Each secondary angleplate 28b is welded for example on two spaced spacers 37 having possiblythe shape shown on FIGURES 5 and 6 and each spacer comprises at itsouter end a recess in the form of a re-entrant dihedron or corner,complementary of the salient corner or dihedron formed by the panels 41,so that it may be secured straddlewise on said salient corner of thebox-like member 34, by the same screws extending through a ange or edgeof said spacers. Particularly on FIGURES 5 to 8 are seen the swaged orcreased portions, joggled machined or cut in the periphery of the angesof the secondary angle plates 28b and adapted to receive the anglepieces 30, So as to be flush with that face of the angle plate 28b whichen gages the angle plate 28a and as in the previous example; each anglepiece 29 or 30 joins by its central corrugation, a correspondingcorrugation of the primary or secondary barrier.

Each assembly 34 may be Prefabricated advantageously at the workshop soas to be ready for erection or mounting in the field. To this end, eachbox-like member 35 is made by temporarily assembling a series of spacerblocks forming cleats 38, for example six in number for each box-likemember, by wooden plates or spacers 47, secured to the various cleats byscrews '48 and joined together, to form angle members, by metal angles49, secured to the plates 47 by bolts 50. On this Igroup of like andaligned cleats are then secured the panels or boards 41, for example bygluing or sticking or by screws and they are connected together by meansof the angle 42 and then they are mounted on the box-like member thusformed by the spacers 37 previously welded to the secondary angle plates28b. Each box-like member having thus been prefabricated separately, allthe hollow spaces or voids, which are inside of the box-like member, arefilled with a heat-insulating material, for example with a synthetic orartificial material, such as a foamed plastic material such as expandedpolyurethane or an equivalent substance, applied by spraying orinjection by means of a spray-gun before setting or mounting eachassembly 34 in the field. During the building of the tank, a subsequentoperation of the method of manufacture or building obviously consist infilling up, with insulating material, for example with expandedpolyurethane, all the space 51 left between the inner wall of thesupporting structure 1 formed for example by the ships hull and thesecondary barrier 16. Outside the corner angle plates or sections, thespace left between the primary and secondary barriers 17 and 16,respectively, is desirably filled up with plates or panels made fromheat-insulating material and compact and rigid enough to sustain orsupport both barriers bearing thereagainst and to serve to distributethe forces and pressures exerted by said barriers. These relativelyrigid or stiff panels or plates consist for example of plywood or ofcompressed, laminated or like wood, 52 (see FIGURE l).

FIGURES 9, l0 and ll show an embodiment of`a corner having the shape ofa solid re-entrant angle, such as a corner in the shape of a re-entranttrihedral angle 53 in the outer supporting structure 1 formed forexample by the double-walled ships hull, to which corresponds there-entrant trihedral angle 53 of the integrated tank. This re-entranttrihedral angle 53 consists, similarly to the configuration of dihedralangles, of two primary and secondary angular elements 54a and 54b,respectively, nested or fitted into each other and joined or connectedtogether in overlying relationship by screws 55, this assembly havingsubstantially the desired geometrical shape for such a re-entranttrihedral corner. This angular assembly is supported in a manner similarto that of the preceding examples, by spacer blocks forming cleats orthe like 56, secured to the inner wall of the hull 1 by pairs of studs57 with clamping or tightening stirrups, clips, dogs, straps or the like58. This angular assembly 54 is thus supported by at least three cleatssuch as 56a, 56b and 56C, straddling the three dihedral angles,respectively, forming the trihedral angular element S4 and these threecleats can advantageously be imbricated mutually into each other in viewof interiitting slots, notches, grooves or like recesses formed to thisend in each cleat, respectively. The angular assembly 54 is secured oneach of these three cleats by tie-rods or like bolts or fasteners 59, inthe manner previously described. Each dihedral angle of the trihedralangular assembly 54 is extended in alignment therewith by the series ofspaced, double angle plates 3, `shown on FIGURES 2 to 4 and on which theprimary and Isecondary barriers are fastened in the manner alreadydescribed. The secondary angular element 54b comprises on the peripheryof its three faces, swaged or creased striplike portions machined as inthe case of the secondary angle plates 3b, and adapted to receive thesecondary barrier metal-sheet 116 bearing thereagainst; likewise, theprimary barrier 17 is applied in a manner similar to that previouslydescribed on the edge of the faces of the primary angular element 54aand the gaps or spacings left between or separating each dihedron of thetrihedral assembly 54 consisting of the adjacent double angle plates 3are respectively covered in overlapping relationship by the primary andsecondary angle pieces 25 and 5, respectively, set or mounted in themanner already described. 'Each one of these angle pieces is secured onthe inner face of the trihedral element 54a by spot or tac-k welds suchas 26. An angle piece 60' of trihedral shape is nested or iitted intoand applied against the inner face of the trihedral element 54a, so asto cover or overlap the adjacent edges of the primary angle pieces 25bearing or applied against this trihedral primary element 54a.

The concept or principle of this construction is obviously applicable toany solid polyhedral angle exhibiting for example more than three facesmeeting at a common point. -In the case of a salient polyhedral angle,the principle of the construction illustrated by the FIGURES 5 to 8 isapplicable while being of course adapted to the case of a salienttrihedral angle.

It is to be understood that the present invention should not beconstrued as limited to the forms of embodiments described herein andshown which have been given by way of illustrative examples only, asmany modifications, alterations and changes may be made by those skilledin or conversant with the art without departing from the scope andteachings of the invention as delined in the appended claims.

What I claim is:

1. A corner construction with at least two meeting sides for a uid-tightcomposite lagged wall separating an inner space from an outer space andcomprising an impervious, relatively thin and flexible membrane-likeprimary barrier bounding said inner space, made of corrugatedsheet-metal, bearing against and spaced from a self-supporting structurebounding said outer space through the medium of at least one layer ofheat-insulating material interposed in and filling the intermediatespace left therebetween, a plurality of substantially rigid, spacerblocks made from heat-insulating material, secured in spacedrelationship to said supporting structure in said intermediate space anddistributed in spaced relationship substantially along each edge line ofintersection of two adjacent sides of said corner, and a plurality ofsubstantially registering metal angle members arranged in at least onerow, having outwardly and inwardly substantially the geometrical shapeof said corner to form same by themselves and secured to said blocks,respectively, said primary barrier being divided along each aforesaidedge line of intersection into at least two separate portions liningsaid meeting sides, respectively, in spaced relation to each other andto said edge line and which are connected in sealing relationship to theend portions of both flanges of each angle member, respectively andmeans for tightly closing each gap left between any two successive anglemembers of each row thereof and the adjacent barrier portions.

2. An arrangement according to claim 1, comprising at least oneimpervious thin and flexible, secondary barrier, made of corrugatedsheet-metal and provided between and in spaced co-extensive relation tosaid primary barrier and supporting structure, at least the secondarybarrier nearest to said primary barrier being divided along eachaforesaid edge line of intersection into at least two separate portionslining said meeting sides, respectively,

in spaced relation to each other and to said edge line and which areconnected in sealing relationship to the end portions of both flanges ofeach aforesaid angle member, respectively, each pair of co-extensiveprimary and secondary barrier portions being connected throughlap-joints to said ilanges, on either side of each flange, respectivelyand means for tightly closing each gap left between any two successiveangle members of each row thereof and the adjacent barrier portions.

3. An arrangement according to claim 2, wherein each barrier portion isconnected to the corresponding ilanges of the associated angle membersby smooth uncorrugated at least marginal areas of said barrier portionseparated by corrugations, respectively, each of which terminates at onegap between two successive angle members and each gap left between thesuccessive angle members of each row thereof is covered at least fromone side by a thin and flexible integral angle piece which is wider thansaid gap and of the same nature as said barrier lying on this side andoverlapping same at least locally while being secured thereto in afluid-tight manner, so as to connect both barrier portions attached toboth flanges of a same angle member, respectively, said angle piecebeing formed throughout with at least one corrugation adjacent to andcontinuously integral with co-extensive plain sections on either sidethereof and extending at and at least along said gap and covering insnugly overlapping and intertting relationship a correspondingcorrugation of the associated barrier.

4. An arrangement according to claim 3, wherein each angle memberconsists of a pair of primary and secondary single piece angle platesnested into and secured in overlying relationship to each other and saidprimary and secondary barriers are connected in sealing relationship tothe flanges of said primary and secondary angle plates, respectively,each primary angle plate being thinner and larger than its associatedsecondary angle plate fitted therein so as to protrude beyond thecorresponding anges of the latter.

5. An arrangement according to claim 4, comprising primary and secondaryangle pieces connected to said primary and secondary barriers,respectively and wherein at least each primary angle piece is longenough in parallel relation to the corner edge so that the successiveangle pieces overlap each other alternately by their adjacent edgeswhich are rigidly connected to each other in a continuous fluid-tightmanner.

6. An arrangement according to claim S, wherein each secondary angleplate is formed on the periphery of each flange thereof, with a thinnedrabbet-like marginal portion forming a stepped ledge, recessed in thatface of the ilange which faces the associated primary angle plate toreceive and seat a corresponding edge portion of said secondary barrieralong said flange and a corresponding edge portion of said angle pieceover the width of said flange, the fastening of said secondary barrierto said flange and of said angle piece to said secondary barrier beingachieved by a continuous weld extending along lapjoint means.

7. An arrangement according to claim 6, wherein each coveringmetal-sheet portion of any assembly thereof having mutually overlappingedges comprises a joggled portion corresponding to the thickness of thecovered metal-sheet portion of said assembly.

8. An arrangement according to claim 7, wherein each primary angle plateis secured to its associated secondary angle plate by screws havingtheir heads sunk into re spective counter-bored recesses and which are,screwed into tapped blind holes of said secondary angle plate andcovered by the associated primary angle piece.

9. An arrangement according to claim 8, wherein said primary barrier issecured to each primary angle plate by spot welds extending through saidbarrier and covered by the associated primary angle piece.

10. An arrangement according to claim 8, wherein said primary barrier issecured to each primary angle plate by screws, having their heads sunkinto respective counterbored recesses and screwed into respectivebacking nut plates, attached to the protruding portion of each ange ofangle plate on the opposite face thereof, said screw heads being coveredby the associated primary angle piece.

11. An arrangement according to claim 8, wherein each primary anglepiece connecting said primary barrier is secured to each primary angleplate by spot welds outside the areas where said angle piece covers saidsecondary barrier.

12. An arrangement according to claim 11 for a corner in the shape of asolid polyhedral angle with at least three faces meeting at a commonpoint, comprising two angular elements nested into each other and joinedtogether in overlying relationship and conforming to the geometricalshape of said corner, said barriers being likewise secured to said angleplates and a covering piece which has the shape of said corner, beingprovided on said primary barrier.

13. An arrangement according to claim 12, wherein said polyhedral angleis a re-entrant trihedral angle provided with three cleats straddlingthe three dihedral angles of said trihedral angles and imbricatedmutually into each other by means of intertting slots formed in eachcleat, respectively.

14. An arrangement according to claim 13, wherein said primary barrierand the secondary barrier nearest thereto are spaced by continuous,stiff, heat-insulating panel means sandwiched therebetween and eachbarrier is formed according to a waffle-like pattern with two sets ofsubstantially parallel spaced corrugations projecting all from a sameside of said barrier, each corrugation of one set intersecting at rightangles the corrugations of the other set, thereby defining smoothuncorrugated areas therebetween, and the corrugations of one setextending parallel to one corner edge line, the corrugations of bothbarriers registering substantially with each other.

15. An arrangement according to claim 11 for a corner having the shapeof a re-entrant angle which is concave towards said inner space andwherein each spacer block consists of at least one apertured openworkconnecting cleat made from a compact material, secured by stud bolts tosaid supporting structure and to which each secondary angle plate isfastened by at least one eye-bolt pivotally connected by means of a pinto a clevis-like bracket integral with said angle plate.

16. An arrangement according to claim 15, wherein said primary barrierand the secondary barrier nearest thereto are spaced by continuous,stiff, heat-insulating panel means sandwiched therebetween and eachbarrier is formed according to a wallie-like pattern with two sets ofsubstantially parallel spaced corrugations projecting all from a sameside of said barrier, each corrugation of one set intersecting at rightangles the corrugations of the other set, thereby defining smoothuncorrugated areas therebetween, and the corrugations of one setextending parallel to one corner edge line, the corrugations of bothbarriers registering substantially with each other.

17. An arrangement according to claim 15, wherein each cleat is a atrigid element bridging said two meeting sides of said corner andrecessed endwise for accommodating and conforming to said secondaryangle plate,

said stud bolts being arranged by pairs on either side face of, adjacentand in parallel registering relation to said cleat so as to clamp a webportion thereof against said self-supporting structure by means of abinding stirruplike clip extending through one aperture of said cleatand straddling one edge of said web portion and connected to said studbolts, said clevis-like bracket straddling the end edge of said cleat,each pin extending through an open notch formed in said end edge of saidcleat and each eye-bolt extending through a bore formed in the thicknessof said cleat and opening at its opposite ends into said notch and intoan aperture of said cleat, respectively, and the nut of each eye-boltbearing against the edge of said aperture through the medium of apressure plate.

18. An arrangement according to claim 17, wherein each cleat comprisesat least one pair of stays of heat insulating material made integralwith said cleat on either side thereof and engaging the outward face ofone flange of the associated secondary angle plate.

19. An arrangement according to claim 14, wherein said primary barrierand the secondary barrier nearest thereto are spaced by continuous,stiff, heat-insulating panel means sandwiched therebetween and eachbarrier is formed according to a waie-like pattern with two sets ofsubstantially parallel spaced corrugations projecting all from a sameside of said barrier, each corrugation of one set intersecting at rightangles the corrugations of the other set, thereby defining smoothuncorrugated areas 30 therebetween, and the corrugations of one setextending parallel to one corner edge line, the corrugations of bothbarriers registering substantially with each other.

20. An arrangement according to claim 11 for a corner v in the shape ofa salient angle which is convex towards said inner space and whereineach aforesaid spacer block consists of a box-like assembly secured tosaid supporting structure and exhibiting inside thereof two facesmeeting at a salient angle similar to said corner and to the meetingedge of which are secured straddlewise therealong, a series of spacedspacer elements supporting said secondary angle plates.

21. An arrangement according to claim wherein each box-like assemblyconsists of a plurality of spaced, apertured connecting cleats securedby stud bolt fasteners to said supporting structure and covered byangular panel means forming a salient angle.

References Cited UNITED STATES PATENTS 1,855,357 4/1932 Kuehn 52-942,254,780 9/ 1941 Quimper 220-15 2,394,229 2/ 1946 Bergstrom 220-152,601,241 6/1952 Boddy 220--15 50 2,737,266 3/1956 Gross 52-2802,892,564 6/1959 Morrison 220-15 3,332,386 7/1967 Massac 220--15 FRANKL. ABBOTT, Primary Examiner JAMES L. RIDGILL, JR., Assistant ExaminerU.S. Cl. X.R.

